Search results for "ACID"
showing 10 items of 13107 documents
Selection of Lactobacillus strains to induce biological acidification in low acidity wines
2016
Abstract Because of global warming, wines are obtained nowadays with high pH values and low acidity. This results in wines with disturbed flavor and increased susceptibility of microbial spoilage. The aim of this work was the selection of Lactobacillus strains with ability to induce biological acidification in low acidity grape musts to obtain more acidic wines. A screening of Lactobacillus strains was carried out using several selection criteria. Lactobacillus strains that grew in must, carried out the malolactic fermentation, acidified grape must, synthesized lactic acid from sugars, and showed high resistance to lysozyme and sulfur dioxide were selected. Selected strains were characteriz…
In vitro antifungal activity of bioactive peptides produced by Lactobacillus plantarum against Aspergillus parasiticus and Penicillium expansum
2017
Abstract Food spoilage caused by mycotoxigenic moulds represents an important problem in food security. The antimicrobial peptides are compounds of natural origin constituted by a variable number (5–100) of amino acids held together through peptide bonds. In this work, the cell free supernatants (CFSs) containing peptides obtained from four strains of LAB were lyophilized, filtered and tested to determine the antifungal activity against Aspergillus Parasiticus and Penicillium expansum . CFS obtained by Lactobacillus plantarum showed the highest inhibition activity. CFS was fractionated by size exclusion chromatography and injected into the liquid chromatography coupled to diode array detect…
Polyamine Biosynthesis Engineering as a Tool to Improve Plant Resistance to Abiotic Stress
2015
Polyamines (PAs) are small polycationic molecules which are present in all living organisms. PAs have been involved in a wide array of metabolic plant processes, extending from development to stress protection. Most of this knowledge has been achieved through the observation of PA homeostasis and manipulation of plant PA levels mediated by different approaches. This chapter summarizes the approaches undertaken to demonstrate the relationship between PAs and the stress response and, in particular, how the genetic manipulation of polyamine levels has evolved in a useful tool for the enhancement of plant stress tolerance in many species, including crops. This chapter also includes the most rec…
Studying the Function of the Phosphorylated Pathway of Serine Biosynthesis in Arabidopsis thaliana
2017
Photorespiration is an essential pathway in photosynthetic organisms and is particularly important to detoxify and recycle 2-phosphoglycolate (2-PG), a by-product of oxygenic photosynthesis. The enzymes that catalyze the reactions in the photorespiratory core cycle and closely associated pathways have been identified; however, open questions remain concerning the metabolic network in which photorespiration is embedded. The amino acid serine represents one of the major intermediates in the photorespiratory pathway and photorespiration is thought to be the major source of serine in plants. The restriction of photorespiration to autotrophic cells raises questions concerning the source of serin…
The In Vitro Interaction of 12-Oxophytodienoic Acid and Related Conjugated Carbonyl Compounds with Thiol Antioxidants
2021
α,β-unsaturated carbonyls interfere with numerous plant physiological processes. One mechanism of action is their reactivity toward thiols of metabolites like cysteine and glutathione (GSH). This work aimed at better understanding these interactions. Both 12-oxophytodienoic acid (12-OPDA) and abscisic acid (ABA) conjugated with cysteine. It was found that the reactivity of α,β-unsaturated carbonyls with GSH followed the sequence trans-2-hexenal <
Gaining Insight into Exclusive and Common Transcriptomic Features Linked to Drought and Salinity Responses across Fruit Tree Crops
2020
The present study aimed at identifying and mapping key genes expressed in root tissues involved in drought and salinity tolerance/resistance conserved among different fruit tree species. Twenty-six RNA-Seq samples were analyzed from six published studies in five plant species (Olea europaea, Vitis riparia Michx, Prunus mahaleb, Prunus persica, Phoenix dactylifera). This meta-analysis used a bioinformatic pipeline identifying 750 genes that were commonly modulated in three salinity studies and 683 genes that were commonly regulated among three drought studies, implying their conserved role in resistance/tolerance/response to these environmental stresses. A comparison was done on the genes th…
An ancestral allele of grapevine transcription factor MYB14 promotes plant defence
2016
Highlight The molecular mechanisms underlying the elevated inducibility of stilbene in pathogen-resistant Vitis sylvestris can be explained by the increased inducibility of the MYB14 promoter.
The Glycerate and Phosphorylated Pathways of Serine Synthesis in Plants : The Branches of Plant Glycolysis Linking Carbon and Nitrogen Metabolism
2018
Serine metabolism in plants has been studied mostly in relation to photorespiration where serine is formed from two molecules of glycine. However, two other pathways of serine formation operate in plants and represent the branches of glycolysis diverging at the level of 3-phosphoglyceric acid. One branch (the glycerate – serine pathway) is initiated in the cytosol and involves glycerate formation from 3-phosphoglycerate, while the other (the phosphorylated serine pathway) operates in plastids and forms phosphohydroxypyruvate as an intermediate. Serine formed in these pathways becomes a precursor of glycine, formate and glycolate accumulating in stress conditions. The pathways can be linked …
The combined effect on initial glucose concentration and pH control strategies for acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobut…
2021
Abstract The use and depletion of fossil fuels raised the interest in biofuels like biobutanol. Clostridium acetobutylicum DSM 792 is capable of producing biobutanol through ABE fermentation. Butanol production can be influenced by low sugar concentrations, like those obtained after hydrolysis of pre-treated lignocellulosic biomass. This study aimed to evaluate the influence of the initial glucose concentrations (33, 66 and 100 g L−1) and pH control strategies on biobutanol production and glucose consumption. Uncontrolled pH fermentation exhibited low butanol production due to either glucose exhaustion (33 g L−1) or the phenomenon of acid crash (66 and 100 g L−1), which was alleviated by th…
Purification, characterization and influence on membrane properties of the plant-specific sphingolipids GIPC
2020
AbstractThe plant plasma membrane (PM) is an essential barrier between the cell and the external environment. The PM is crucial for signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols and phospholipids. The most abundant sphingolipids in the plant PM are the Glycosyl Inositol Phosphoryl Ceramides (GIPCs), representing up to 40% of total sphingolipids, assumed to be almost exclusively in the outer leaflet of the PM. In this study, we investigated the structure of GIPCs and their role in membrane organization. Since GIPCs are not commercially available, we developed a protocol to extract and isolate …